We open our eyes and we instantly perceive a rich and stable world. This happens so effortlessly that we often take for granted the challenges that our visual systems face in piecing together what we see from the light that lands on our retinas. Visual attention and visual working memory are crucial resources without which this process would be impossible. So much information enters our eyes that the visual system would get nowhere if it tried to analyze it all. Attention and memory preclude this kind of information overflow by processing and storing only relevant information. But how do attention and memory know exactly which bits of the world are the relevant ones? Part of the answer is that they operate over important units in visual experience, and a central project in cognitive science is to determine what are the units that attention and memory select. This important question has received a significant amount of research, and current evidence suggests that, at least in some situations, attention and memory operate over bound object representations. They are object-based. However, most research has focused on the static nature of objects, typically contrasting bound objects with unbound features and locations in space. This neglects the intrinsically dynamic nature of objects in real-world experience. The proposed research seeks to expand our conception of what it means to be an object to include the important fact that objects maintain their identities over time despite motion, occlusion, and changes in appearance. Thus the proposed research explores the rules and mechanisms that support the construction and maintenance of persisting object representations. Moreover, the proposed experiments explore persisting object representations by focusing on their consequences for attention and memory. This reflects a new way of characterizing these resources. Rather than asking independent questions about the underlying nature of attention and memory, the proposed project looks at both of these crucial resources from a unifying perspective. Thus a central aim of this project is to demonstrate that representations of persisting objects comprise a piece of the underlying vocabulary of cognition, ultimately guiding how we attend to the world, how we remember it, and even how we reason about it. The results of these experiments will have implications for our understanding of disorders where basic resources such as attention and memory are impaired (e.g. ADHD, Alzheimer's disease). These results will also have implications for the effective presentation of information, especially in the design of interventions for impaired populations and in the design of interfaces for cognitively demanding situations (e.g. air-traffic control). [unreadable] [unreadable] [unreadable]